= Test channel
{disambiguate=information theory}
{title2=$p_{\widehat X\mid X}$}
= Test channel
{synonym}
A <test channel> is a proposed <conditional distribution> of a reconstruction given the source symbol. It describes a candidate joint <probability distribution> for evaluating <mutual information> and <expected distortion>. It need not be a physical transmission <channel>, or an implementable one-symbol <encoder>; the <Shannon rate-distortion theorem> relates this optimization to long <block codes>.
Back to article page
